Molecular sieves having the STI framework topology defined by the connectivity of the tetrahedral atoms (referred to herein simply as “STI”) are known. See, for example, Ch. Baerlocher et al., Atlas of Zeolite Framework Types, 6th Revised Edition, 2007 of the International Zeolite Association. Examples of STI molecular sieves include naturally occurring stilbite, the zeolite designated TNU-10, and the molecular sieve designated SSZ-75. Stilbite is disclosed by D. W. Breck, Zeolite Molecular Sieves: Structure Chemistry and Use 1984, Robert E. Krieger Publishing Company. TNU-10 is reported by S. B. Hong et al., J. Am. Chem. Soc. 2004, 126, 5817-5826. SSZ-75 is disclosed in U.S. Pat. No. 7,713,512.
Because of their unique sieving characteristics, as well as their catalytic properties, crystalline molecular sieves and zeolites are especially useful in applications such as hydrocarbon conversion, gas drying and separation. Although many different crystalline molecular sieves have been disclosed, there is a continuing need for new molecular sieves with desirable properties for gas separation and drying, hydrocarbon and chemical conversions, and other applications. New molecular sieves may contain novel internal pore architectures, providing enhanced selectivity in these processes.